The World’s Biggest Laser Powers Up

The most energetic laser system in the world, designed to produce nuclear fusion–the same reaction that powers the sun–is up and running. Within two to three years, scientists expect to be creating fusion reactions that release more energy than it takes to produce them. If they’re successful, it will be the first time this has been done in a controlled way–in a lab rather than a nuclear bomb, that is–and could eventually lead to fusion power plants.